• 한국해양학회지
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• v.20 no.2
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• pp.28-39
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• 1985

The driving mechanisms for low level jets(LLJ) and coastal surface maximum winds are studied with observed wind data from June, 1976 through August, 1980 at Port Aransas and Victoria, Texas, in connection with a baroclinic model. This model is developed considering the forcing functions such as the synoptic and meso-scale pressure gradient, the frictional force, and the atmospheric stability. The results show that a LLJis observed on over 95% of the occasions when a nighttime coastal wind maximum occurred. Baroclinicity generated by sloping terrain during the summertime causes the diurnal variation in the thermal field. This thermal wind component would then decrease the prevailing synoptic-scale southerly wind by day and allow it to increase at night. Nighttime atmospheric stability leads to frictional decoupling which enhances the nocturnal LLJ. At the coastal site neutral stability prevails, thus all owing downward transfer of momentum from the nocturnal LLJ and results in the nocturnal coastal surface wind maximum. The height of LLJis not uniquely related to the inversion layer, and the results of the computations using this model show a good agreement with the observations.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2003.04a
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• pp.195-198
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• 2003

자갈축열 태양열온실은 주간에 일사로 데워진 온실 내부공기를 온실하부에 설치된 자갈축열층사이로 강제순환시켜 자갈에 에너지를 축열한다. 이러한 축열과 방열과정을 통하여 겨울철 야간에 난방시스템으로 이용하고, 여름철에는 냉방효과를 꾀하게 된다. 온실내 공기가 축열층을 통과하는 동안의 열전달은 강제대류열전달이며, 이 경우 축열층내의 열이동은 축열층내 공기와 자갈표면온도가 초기에는 열적으로 평형상태로 존재하다가 순환공기의 온도상승에 따라 열전달이 일어나게 된다. (중략)

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.5
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• pp.420-424
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• 2006

This experiment was conducted to elucidate the basic physiological phenomena of pollination and fertilization for breeding in perilla (Perilla frutescens) through different 6 varieties derived from 2 genera under 4 temperature conditions at day and night. The pollen germination was observed after 30 minutes and pollen tube reached the lower part of pistil after 1 hour from artificial pollination. Seed formation was affected by temperature condition and a variety. The early maturing variety 'YCPL 25' showed a poor seed formation rate under the night temperature below $15^{\circ}C$, but the late maturing variety 'YCPL263' did not lowered even though the night time temperature was $10^{\circ}C$. The function of pistil was long maintained under the low temperature from the fact that if the live pollen pollinate artificially to the flower that does not form seed under low temperature, fruiting was made. Pollen was created and pollen tube was developed in the time of petal becomes bigger than calyx in five varieties, 'YCPLl77-1' etc. However, pollen was made and pollen tube was made only 71% in a green chajogi 'YCPL205-1'. These physiological phenomena of pollination and fertilization could be applicable to the emasculation and an effective breeding in perilla.

• Journal of Bio-Environment Control
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• v.6 no.1
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• pp.15-25
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• 1997

Plug seedlings of bell pepper(Capsicum annuum L.) were grown for 50 days in controlled environment chambers under 12 hrs per day photoperiodic condition with sixteen different day and night temperature regimes to investigate the possibility of height control. The seedlings were then transplanted to greenhouse to investigate the growth, flowering, and yield afterward. Plant height and stem length of seedlings were mainly affected by day temperature rather than night temperature. Internode elongation was suppressed by a negative DIF and was enhanced by a positive DIF even with the same average daily temperature (ADT). Leaf unfolding rate was influenced more by ADT than by DIF. Fresh and dry weights increased as ADT increased. Leaf area and stem diameter increased until temperature increased up to 24$^{\circ}C$ day and night temperature and decreased above 24$^{\circ}C$, The position at which the first flower was initiated was lowered as ADT increased. The first flower degeneration was not obvious up to 24$^{\circ}C$ ADT but increased rapidly above 24$^{\circ}C$ ADT. Seedling compactness(Dry weight per plant height :mg.mm$^{-1}$ ) was greater under -DIF than +DIF condition. In conclusion, DIF treatment was an applicable technique to control stem elongation and growth rate such as leaf unfolding rate and position at which first flower was initiated could be controlled by ADT.

• Journal of Bio-Environment Control
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• v.13 no.4
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• pp.226-232
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• 2004

This experiment was conducted to investigate the effect of night and daytime temperatures on growth and yield of paprika 'Fiesta' and 'Jubilee' under soil culture experiment in the vinyl houses during the 2003 and 2004 season. Total fruit yield was greater in 'Fiesta' than 'Jubilee' Marketable yield was not different between two cultivars, due to lower $\%$ marketable fruits in 'Fiesta'. mean Fruit weight was not different between two cultivars. Difference of yield between cultivars was due to fruit number, harves time and root condition. It was caused by cracked fruits to decrease $\%$ marketable fruits. Total yield was greater in nighttime temperature of $18^{\circ}C\;than\;15^{\circ}C$ and marketable yield was considerably greater because of $\%$ marketable fruits was higher. Mean fruit weight was slightly greater in nighttime temperature of $15^{\circ}C\;than\;18^{\circ}C$. Difference of fruit yield in treatments of nighttime temperature was due to fruit number and harvest time. There was not significant difference of yield between daytime temperature of $28^{\circ}C\;and\;31^{\circ}C$, but in $34^{\circ}C$, total and marketable yields were the least and mean fruit weight was the smallest because of decreased $CO_2$ concentration in the house, accerated vegetative growth, and the least chlorophyll content. There were no significant difference in photosynthetic rate, transpiration rate, maximal photochemical efficiency and antioxidant enzyme activities of all temperature treatments in this experiment. However it was clear that a little difference in error range of these results affects the source of crops in any case. It was not acknowledged that compensation effect by high temperature in daytime to the low temperature treatment in nighttime.

• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.328-334
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• 2021

This study was conducted to analyze the effect of fog cooling during daytime and heatpump cooling at night in greenhouses in summer. During daytime, the average temp. and RH of the control greenhouse which had shading screen were 32.1℃ and 59.4%. and the average temp. and RH of the test greenhouse which had fog cooling were 30.0℃ and 74.3%. At this time, the average outside temp. and RH were 31.4℃ and 57.7%. So, the temp. of the control was 0.7℃ higher than outside temp., but the temp. of the test was 1.4℃ lower than outside and 2.1℃ lower than control. The average RH was 74.3% in the test and 59.4% in control. The average temp. and RH of the control greenhouse which had natural ventilation at night were 25.2℃ and 85.1%, and the average temp. and RH of the test greenhouse which had heat pump cooling were 23.4℃, 82.4%. The average outside temp. and RH at night were 24.4℃ and 88.2%. The temp. of the control was 0.8℃ higher than outside temp., but the temp. of the test was 1.0℃ lower than outside and 1.8℃ lower than control. The average RH was 82.4% in test and 85.1% in control greenhouse. There was no significant difference between the plants growth eight weeks after planting. But after the cooling treatment, the values of stem diameter, plant height, chlorophyll in test were higher than control. The total yield was 81.3kg in test, 73.8kg in control, so yield of test was 10.2% higher than control. As a result of economic analysis, 142,166 won in profits occurred in control greenhouse, but 28,727 won in losses occurred in test greenhouse, indicating that cooling treatment was less economical.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.4
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• pp.439-444
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• 1983

Effects of temperature and soil moisture on the growth and grain-filling of two wheat cultivars were investigated. Two levels of temperature; day 3$0^{\circ}C$/night $25^{\circ}C$ and day 2$0^{\circ}C$/night 15$^{\circ}C$ and two levels of soil moisture; stressed (45-50% of F.C.) and non-5tressed (50-60% of F.C.) were imposed in the green house from heading date to the maturity and grain weight, chlorophyll content of flag leaf and leaf area index(LAI) were observed at weekly interval. Grain maturation was faster in the high temperature than those in the lower temperature. Chlorophyll content of flag leaf and LAI decreased rapidly in the high temperature and chlorophylls disappeared at the 20 days after heading. In lower temperature condition, slower decrements were shown in chlorophyll content and it remained until 45 days after heading. Grain weights in the high and optimum temperature conditions reached to maximum values at 29 days and 45 days after heading, respectively. Differences of grain weight and chlorophyll content of flag leaf were not significant between stressed and non-5tressed soil moisture condition.

• Journal of Animal Environmental Science
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• v.7 no.3
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• pp.155-164
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• 2001

Environmental factors such as $NH_3,\;H_2S,\;CO_2$, dust, temperature, and humidity in the animal house are a potential health hazard to humans and animals. Until now, most of measurement methods can only provide periodic results with low accuracy. A data acquisition system which can measure continuously and simultaneously $NH_3,\;H_2S,\;CO_2$, temperature, and humidity was developed and installed in two pig houses. Daily changes of environment for the pig-houses were investigated by the data acquisition system. In order to evaluate NH$_3$sensor, gas samples were obtained and NH$_3$concentrations were measured at nine positions; combinations of three positions(inlet, middle, and outlet) and three heights(0 cm, 40 cm, 150 cm). Ammonia concentration of 14.0 ~37.1 ppm for slurry pig-house is higher than that of 8.4~29.7 ppm for scraper pig-house, and there were no statistical differences among the positions. However, the concentration of $NH_3$at 150 cm was higher than thats of 0 cm and 40 cm.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.1
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• pp.7-18
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• 2006

This study aims to analyze the illumination effects of bridges across the Han River. For the purpose, 8 bridges were selected. Field survey and measurements were performed, and the physical values such as luminance, color temperature and chromaticity were measured by Radiant Imaging Prometric 1400 Color. The results of the study are as follows; (1) Metal halide lamp, sodium lamp and LED(Light Emitting Diode) of various colors, are used in illuminating the bridges and create color contrasts and color changing by color filters. (2) Luminance contrast of the illuminated bridges affects 'modeling' and 'spare sense' of bridges, and it might improve people's preference and impression. (3) Color temperature of the illuminated bridges is influenced by 'color of bridge', 'material of bridge' and, 'color temperature and color of light sources'. (4) 'Structure of bridges' and 'luminaires' influence on the physical feature of the bridges. Especially, illumination of the bridges shows resemblant patterns by 'structure of bridges'.

• Journal of Bio-Environment Control
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• v.7 no.1
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• pp.71-77
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• 1998

The root-zone environment is an important factor to the plant growth and it is closely related to the thermal characteristics of the root media. In this study thermal characteristics of root media with ambient environmental conditions were analyzed. The temperatures of nutrient solution as well as inside air of culture bed were measured in Nutrient Film Technique(NFT) and Deep Flow Technique(DFT) systems, and also the temperatures of root media measured in aggregate culture systems , The temperature of nutrient solution of NFT system with as low as 3$\ell$/min of flow rate was 3$^{\circ}C$ higher than that with 5 $\ell$/min of flow rate in the daytime, and the temperature of inside air was 2$^{\circ}C$ higher at night. And the temperature of nutrient solution of DFT system with as low as 0.8 cm of water level was 1-2$^{\circ}C$ higher than that with 1 8 cm in the daytime, and the temperature of inside air was almost same at night. The root-zone temperatures in the perlite and rockwool granulate systems with film mulching were 3$^{\circ}C$ higher than those without film mulching in the daytime. However, the rockwool slab system with film mulching showed the same trend as rockwool granulate system, but relatively higher temperature than any other medium because of the exposure of media surface to the ambient air. Additionally the temperature below the plant was measured 3$^{\circ}C$ lower than that between plants.